" The advent of agriculture and civilization caused life expectancy to drop significantly, reaching a low of 18 during the Bronze Age of 3,300 B.C. to 1,200 B.C.. Life expectancy remained low (between 20 and 30) through 1500 A.D. and then climbed only gradually, reaching ~30 in 1800 and ~40-50 in 1900 in the USA and Europe. "

― Mark Sisson , The Primal Blueprint: Reprogram Your Genes for Effortless Weight Loss, Vibrant Health, and Boundless Energy